Hairy wart disease is an infectious disease that propagates among cows and other ungulates. Digital dermatitis (DD) is known to be a particularly serious hoof and leg disease caused by bacteria belonging to the genus Treponema, and in the case dairy cows have become afflicted with this disease, can lead to serious gait disorders or weight loss and the like as well as cause decreased milk production, thereby making it a serious problem in numerous dairy product-producing countries including Japan. As methods used to prevent and/or treat hairy wart disease in dairy cows, a foot bath wherein hoof baths containing medicinal agents, such as sodium alginate, copper sulfate, slaked lime or antibiotics (such as lincomycin) are placed in a barn and dairy cows are allowed to pass there through, is currently employed. However, effects in the case of using sodium alginate, copper sulfate or slaked lime are not satisfactory, and although effects are superior in the case of using antibiotics, there are problems such as the risk of the generation of drug-resistant microorganisms and the risk of milk being polluted through antibiotics. In addition, although, for example, a prevention and/or treatment method using peroxycarboxylic acid disclosed in Patent Document 1, a prevention and/or treatment method using a working liquid containing a metal astringent disclosed in Patent Document 2, and a prevention and/or treatment method using a composition containing a crosslinking agent disclosed in Patent Document 3 have been proposed, it is currently extremely important to develop a more effective prevention and/or treatment method.